I think that's the fate of every project like that. Not to take away from it, it's still fantastic and geeky. But at some point, you have this realization that you're pouring years of your life into something that is not only utterly useless, but also won't be appreciated by others. You can't even play Pong on it. There's literally nothing you can demo to non-nerds, other than "this device makes looks complicated and makes noise".
Maybe you'll make it to HN more than a decade later, but that's it. No one will buy it from you. Your heirs will toss it out. It... sucks.
The real project is the sense of accomplishment we gained along the way, or something like that.
But anyway, there are institutions like the Craftsmanship Museum <https://craftsmanshipmuseum.com/> that exist to present this kind of passion project to the interested public. That one in particular came out of and is still very centered on the hobby machinist and model steam engine community... if there's not already something similar for electronics and computing type projects, it definitely seems like maybe there could/should be.
And yet you've developed this knowledge for yourself that applies to other things. Among them you develop probably the most imperative skill which practically nobody focuses on; problem solving. And if you've got kids that share your interests they get that knowledge and experience also.
Humans need hobbies. Humans need to explore their curiosities. If you're not doing this you're hiking or biking or gaming or going to the gym or kayaking or.... something equally useless.
I really feel this statement. I'm being forced out of a company that is struggling to pay my salary, after almost 18 years. This is a career where I taught myself and continued (and continue) to improve. I know that my best skill is the ability to solve unique problems, and that's mostly been from needing to complete a project or the business loses their time and money. For most of my career, I have been the sole developer, and impostor syndrome is real and haunting. Having HN, and following various news and blog sources, I think I am in a good place with my knowledge. It's just transferring to another company after almost two decades that is the scary part.
Having a senior position, but still very much wanting to be involved in coding and architecture, makes me nervous that I won't be able to keep my same lifestyle without going into full-time management. Problem solving is often tossed to the side for a "good enough" answer. I understand that as a business need, but when things start to get really complicated, pulling in an existing library or solution is often not possible.
Sure, but we're herd animals and also need validation, even if we're pretending not to. We go on a journey of self-discovery to Nepal so that we can talk to others how profound it was, etc.
I'm not dissing hobbies, I'm just saying that building stuff like that is a very lonely hobby, which is why such projects almost always fizzle out.
Who's to say no one appreciates it? And even if it were unappreciated, that doesn't make it any less worthwhile to the person working on it if that's what they choose to do with their time. Not every project needs to live forever with a bustling community and updates. You can quietly work on something, finish it one day, be proud of your work, and put it online for others to admire (or not). That's plenty enough of a purpose and reason to build these things IMO.
Maybe you'll make it to HN more than a decade later, but that's it. No one will buy it from you. Your heirs will toss it out. It... sucks.